Journal of Dental Research, Vol 67, 1122-1125, Copyright © 1988 by International & American Associations for Dental Research Online Journals
Comparison of solution- and gel-prepared enamel lesions--and in vitro pH-cycling study
F. A. Damato, R. Strang and K. W. Stephen
Department of Oral Medicine and Pathology, University of Glasgow Dental Hospital and School, Scotland.
A variety of methods has been employed to produce artificial caries-like
enamel lesions. The aim of this paper was to use a pH-cycling regime to
compare the de-/remineralization behavior of lesions prepared by two
methods. Lesions were produced by use of either an acidified undialyzed
gelatin system or a buffered solution. Enamel sections, each containing
four lesions, were allocated to four groups (A, B, C, D) and subjected to a
daily pH-cycling regime of 16-hour demineralization and eight-hour
remineralization. Groups A & B contained gelatin-prepared lesions,
whereas Groups C & D contained solution-prepared lesions. To the
remineralizing solutions used in Groups B & D, 2 ppm fluoride was
added. The mineral content in the lesions was assessed, by means of
microradiography/microdensitometry, at baseline and at intervals for six
weeks. The lesions in all four groups exhibited net demineralization. In
terms of the total mineral lost from the lesion (the delta z parameter),
the demineralization rates of the solution-prepared lesions were
significantly greater than those of the corresponding gelatin-prepared
lesions. All sections in the non-fluoride groups showed subsurface
demineralization in initially sound enamel, whereas only one section in the
fluoride groups showed an area of mineral loss. Laminations in the mineral
content profiles were apparent only in Group D. The results of this study
indicate that the method of lesion preparation affects the subsequent
behavior of lesions when exposed to de- and remineralizing protocols.
